High inter-port isolation dual circularly polarized slot antenna with split-ring resonator based novel metasurface

In this paper, a Dual Circularly Polarized (DCP) full-duplex planar slot antenna suitable for C-band applications is presented. The antenna has a single slot with a T-shaped stub that is shared by both the transmitting (T-x) and receiving (R-x) ports which operate at two mutually orthogonal circular polarizations. A metasurface made up of 4 pairs of face-to-face Split Ring Resonators (SRRs) acts as a decoupling network to enhance the isolation between T-x and R-x ports. The designed antenna has an impedance bandwidth of 1340 MHz which is 28.52% of centre frequency f(0) = 4.71 GHz. The 3 dB axial ratio (AR) bandwidth is 8.97% centred at f(AR) = 4.44 GHz whereas inter-port isolation is better than 27 dB and reaches up to 36 dB within the usable band. The proposed design also exhibits characteristics suitable for MIMO applications. (C) 2019 Elsevier GmbH. All rights reserved.